Помогите чекнуть 2 миллиарда строк. Как лучше?

var useragent = project.Variables["UserAgent"].Value;

int count = 0;
int count2 = 0;

for (int i = 0; i < 1000; i++)
{
    if (Global.Variables.IsProjectMaker && !Global.Variables.IsDebugMode) throw new Exception();
    if (((ZennoLab.InterfacesLibrary.ProjectModel.Collections.IContextExt)project.Context).IsInterrupted) throw new Exception();
               
    var pages = new List<object>().Select(t => new { Count = default(int) }).ToList();
    for (int j = count; j < count2 + 50; j++)
    {
        count++;
        pages.Add(new { Count = count });
    }
    count2 = count;
   
    var sb = new StringBuilder();
    System.Threading.Tasks.Parallel.ForEach(pages, p =>
    {
        using (var request = new HttpRequest())
        {
            try
            {
                var url = "https://yandex.ru/";
               
                request.ReconnectLimit = 3;
                request.ReconnectDelay = 50;
               
                request.KeepAlive = true;
                request.UserAgent = useragent;
                request.AllowAutoRedirect = true;
                request.IgnoreProtocolErrors = true;
                request.EnableEncodingContent = true;
                request.MaximumAutomaticRedirections = 5;
               
                request["Upgrade-Insecure-Requests"] = "1";
                request["Accept-Language"] = "ru-RU,ru;q=0.9,en-US;q=0.8,en;q=0.7";
                request["Accept"] = "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3";
               
                bool status = request.Get(url).IsOK;
               
                if (status)
                {
                    project.SendInfoToLog("", "Status -> " + status + " -> Count -> " + p.Count.ToString(), true);
                    sb.Append(p.Count.ToString() + "|");
                }
            }
            catch (HttpException e)
            {
                string answer = string.Empty;
                switch (e.Status)
                {
                    case HttpExceptionStatus.Other:
                        answer = "Неизвестная ошибка";
                        break;
                    case HttpExceptionStatus.ProtocolError:
                        answer = "Код состояния: " + (int)e.HttpStatusCode;
                        break;
                    case HttpExceptionStatus.ConnectFailure:
                        answer = "Не удалось соединиться с HTTP-сервером";
                        break;
                    case HttpExceptionStatus.SendFailure:
                        answer = "Не удалось отправить запрос HTTP-серверу";
                        break;
                    case HttpExceptionStatus.ReceiveFailure:
                        answer = "Не удалось загрузить ответ от HTTP-сервера";
                        break;
                }
                project.SendErrorToLog("", answer, true);
            }
        }
    });
   
    project.SendInfoToLog("", "Обработанно " + count2 + " страгиц", true);
   
    var list = sb.ToString().Split(new string[]{ "|" }, StringSplitOptions.RemoveEmptyEntries);
    FileSystem.FileAppendString(project.Directory + "\\Result.txt", string.Join("\r\n", list), true);
}